I would connect an amprobe meter on your load wires the breakers are feeding and see what kind of load is on your breakers. If they are kicking prematurely then you would need a new breaker. You also need to check your connections at the breakers and other connections. A loose connection or corroded connection will cause excessive heat and cause the breakers to kick.
So back to your question, there should be an access cover to get to the connections and think you need to start there. I’m thinking if your generator is similar to one of my generators I have owned you may have to remove part of the generator shroud to access the breaker for removal.
I do not know your particular generator so I am trying give the best thoughts from my previous experiences. Hopefully this gives you some where you start.
2005 CC Affinity 770, 2006 Jeep TJ
2015 Newmar Essex 4553